Z87 (ANSI/ISEA Z87.1) is the US safety-eyewear standard referenced by OSHA, and Z94.3 is the equivalent Canadian standard published by the Canadian Standards Association; both are tested by firing a steel ball at the lens, but Z94.3 mandates a larger side-coverage area on the frame than the basic US spec [S3].
The "+" suffix is an impact-rating distinction, not a region distinction: Z87 covers basic impact protection, while Z87+ certifies the lens and frame to a higher-velocity impact test under the same ANSI/ISEA Z87.1 document, and is required where flying debris or high-speed projectiles are present [S1].
What Z87 and Z94.3 Actually Mark on the Lens
Every compliant pair of safety glasses is permanently marked on the frame or lens. US-market eyewear carries a Z87 or Z87+ stamp under ANSI/ISEA Z87.1, and Canadian-market eyewear carries a Z94.3 stamp under CSA Z94.3 [S3].
Z87+ is not a separate standard; it is a higher tier inside the same ANSI/ISEA Z87.1 document, reserved for products that survive the high-mass and high-velocity impact tests rather than only the basic drop-ball test [S1]. The "+" suffix is the difference between "occupational" and "industrial" or impact-rated eyewear in the US hierarchy. In practice, a Z87+ lens can also carry a CSA Z94.3 mark when the same SKU is dual-certified for cross-border crews [S2].
Region, Regulator, and Legal Acceptance
OSHA in the United States requires employers to follow ANSI/ISEA Z87.1; OSHA does not test or approve individual products itself, so a Z87 or Z87+ mark is what auditors look for on US sites [S3].
In Canada, the Canadian Centre for Occupational Health and Safety (CCOHS) and provincial regulators reference CSA Z94.3, and a US-only Z87+ pair is not, on its own, compliant for a Canadian site [S3]. A lens stamped only Z94.3 will not satisfy a US OSHA inspection, and a lens stamped only Z87+ will not satisfy a Canadian inspection; the safest path for crews that cross the border is dual-marked product [S2].
Side-Shield and Frame Coverage Rules
CSA Z94.3 demands more extensive side protection than the basic US standard, with a larger peripheral coverage area to keep dust, wood chips, and metal shavings out of the gap between the frame and the face [S3].
ANSI/ISEA Z87.1 also requires side protection for impact applications, but it permits a smaller side-coverage geometry, which is why the same impact-rated lens can look like a flatter, more wrap-around frame under Z94.3 than under Z87+ [S3]. This is the most visible physical difference on the shelf, and it is the one auditors tend to flag first when a Canadian worker shows up in a US-style frame. Readers comparing PPE categories more broadly can see the same jurisdiction-versus-spec pattern in this PPE spec breakdown for safety glasses.
Impact Test Mechanics: How Similar the Two Really Are
Both standards use a steel-ball projectile test against the lens, and the lens strength numbers are close, which is why many safety managers assume the marks are interchangeable [S3].
The divergence is in the frame and peripheral zone: CSA Z94.3 layers on additional criteria for side coverage and plastic-degradation behaviour that are not mirrored one-for-one in ANSI Z87.1, so passing one is not a guarantee of passing the other [S3]. For workplaces that need both, look for explicit dual marking (Z87+ and Z94.3 on the same temple or lens), and treat that as the procurement requirement rather than relying on test reports alone.
Criteria Comparison: Z87+ vs Z94.3 Side by Side
The table below lines the two up on the four decision criteria a safety manager actually has to defend in an audit: region, regulator, side coverage, and on-lens marking [S3].
Region: Z87+ applies in the United States, Z94.3 applies in Canada. Regulator: Z87+ is referenced by OSHA, Z94.3 is referenced by CCOHS and provincial bodies. Side coverage: Z87+ allows a smaller side-coverage area, Z94.3 requires a larger one. Marking: Z87+ reads "Z87+" on the frame or lens, Z94.3 reads "Z94.3" [S3]. For buyers who also have to think about adjacent PPE, the construction-machinery and equipment reference page covers parallel jurisdiction logic for other regulated gear on the same job site.
When Z87+ Is Required and When Z94.3 Is Required
Z87+ is required in US environments with flying debris or high-speed projectiles, including grinding, chipping, masonry, and most machining tasks; basic Z87 (without the plus) is only the occupational, non-impact-rated tier [S1].
Z94.3 is the floor for any Canadian workplace where eye protection is mandated, and the stricter side-coverage rule means a US basic-Z87 frame may not be acceptable even when the lens impact rating looks equivalent [S3]. Sectors that work across both markets, such as cross-border construction, oil and gas field services, and rail maintenance, should standardize on dual-marked product to avoid two separate SKU inventories [S2].
Limitations, Common Mistakes, and Sourcing Checks
The most common procurement mistake is treating "Z87+" and "Z94.3" as competing certifications of the same thing; they are not, because one is a US impact tier and the other is a Canadian national standard with its own frame rules [S3].
A second common mistake is assuming a CE-marked European spectacle is a substitute: CE EN 166 is the EU reference, and while many products carry Z87+ and CE side by side, the Canadian Z94.3 mark still has to be present for Canadian acceptance [S2]. Buyers should also verify the mark is permanent (stamped, not printed on packaging) and check the lot-level documentation from the manufacturer, because counter-stamped Z87+ glasses remain a known audit failure mode. Related inspection gear, such as the lamps and light fittings and lighting equipment and electric lamps categories, follow a similar logic where jurisdiction and stamp legibility determine acceptance.
Next signal to track: any 2026 revision activity on CSA Z94.3 (the prior major revision aligned the impact test geometry closer to ANSI Z87.1) and any OSHA interpretive letter clarifying acceptance of dual-marked Z87+ / Z94.3 product at US sites; both would shift the procurement checklist above. For now, dual-marked Z87+ and Z94.3 product remains the lowest-friction path for cross-border crews.
Background reading: Print-and-Apply Labeler vs Pre-Printed Label Applicator: Selection Spec Guide.